I have more than 19,000 hours of flight time, much of it at night above 33,000 feet. I have always been alert for anything unexplained in the night sky, or in the daytime for that matter, because I do believe we are not alone in the universe. I have never seen a UFO, or anything I couldn't eventually explain. That anecdotal testimony is insignificant to the central question: are we being observed by another, more advanced civilization? The pivotal problem, I believe, is our inability to get beyond Einstein's theories regarding the speed of light. I certainly don't conclude that because we haven't done that, we won't eventually do it. Or that other civilizations have not already done it. If you are interested in the idea of the probability of other intelligent life in the universe, I strongly recommend Isaac Azimov's book, "Extraterrestrial Civilizations".
